U.S. patent number 10,047,831 [Application Number 15/333,371] was granted by the patent office on 2018-08-14 for planetary gear train of automatic transmission for vehicles.
This patent grant is currently assigned to Hyundai Motor Company. The grantee listed for this patent is Hyundai Motor Company. Invention is credited to Wonmin Cho, Seong Wook Hwang, Wookjin Jang, Seongwook Ji, Jae Chang Kook, Hyun Sik Kwon, Woochurl Son.
United States Patent |
10,047,831 |
Kook , et al. |
August 14, 2018 |
Planetary gear train of automatic transmission for vehicles
Abstract
A planetary gear train of a transmission for a vehicle is
provided. Nine or more forward speeds and one or more reverse
speeds are achieved by a planetary gear train of an automatic
transmission for a vehicle including an input shaft and an output
shaft. A first planetary gear set has first, second, and third
rotation elements. A second planetary gear set has fourth, fifth,
and sixth rotation elements. A third planetary gear set has
seventh, eighth, and ninth rotation elements. A fourth planetary
gear set has tenth, eleventh, and twelfth rotation elements and
eight shaft element.
Inventors: |
Kook; Jae Chang (Gyeonggi-do,
KR), Hwang; Seong Wook (Gyeonggi-do, KR),
Son; Woochurl (Gyeonggi-do, KR), Cho; Wonmin
(Gyeonggi-do, KR), Kwon; Hyun Sik (Seoul,
KR), Jang; Wookjin (Gyeonggi-do, KR), Ji;
Seongwook (Gyeonggi-do, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
Hyundai Motor Company |
Seoul |
N/A |
KR |
|
|
Assignee: |
Hyundai Motor Company (Seoul,
KR)
|
Family
ID: |
59855465 |
Appl.
No.: |
15/333,371 |
Filed: |
October 25, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170268628 A1 |
Sep 21, 2017 |
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Foreign Application Priority Data
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Mar 16, 2016 [KR] |
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10-2016-0031663 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16H
3/66 (20130101); F16H 3/666 (20130101); F16H
2200/0065 (20130101); F16H 2200/2046 (20130101); F16H
2200/2012 (20130101) |
Current International
Class: |
F16H
3/66 (20060101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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10-2012-0132021 |
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Dec 2012 |
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KR |
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2013/146028 |
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Oct 2013 |
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WO |
|
Primary Examiner: Knight; Derek Douglas
Attorney, Agent or Firm: Mintz Levin Cohn Ferris Glovsky and
Popeo, P.C. Corless; Peter F.
Claims
What is claimed is:
1. A planetary gear train of an automatic transmission for a
vehicle, comprising: an input shaft configured to receive power of
an engine; an output shaft configured to output power; a first
planetary gear set having first, second, and third rotation
elements; a second planetary gear set having fourth, fifth, and
sixth rotation elements; a third planetary gear set having seventh,
eighth, and ninth rotation elements; a fourth planetary gear set
having tenth, eleventh, and twelfth rotation elements; a first
shaft connected with the first rotation element and the fourth
rotation element and selectively connected with the input shaft or
selectively connected with a transmission housing; a second shaft
connected the second rotation element and the sixth rotation
element and the seventh rotation element and the tenth rotation
element; a third shaft connected with the third rotation element
and selectively connected with the input shaft; a fourth shaft
connected with the fifth rotation element; a fifth shaft connected
with the ninth rotation element; a sixth shaft connected with the
eighth rotation element and directly connected with the output
shaft; a seventh shaft connected with the eleventh rotation element
and directly connected with the input shaft; and an eighth shaft
connected with the twelfth rotation element and selectively
connected with the sixth shaft.
2. The planetary gear train of claim 1, wherein the fourth shaft
and the fifth shaft each are selectively connected with a
transmission housing.
3. The planetary gear train of claim 1, wherein: the first, second,
and third rotation elements of the first planetary gear set are a
first sun gear, a first planetary carrier, and a first ring gear,
respectively, the fourth, fifth, and sixth rotation elements of the
second planetary gear set are a second sun gear, a second planetary
carrier, and a second ring gear, respectively, the seventh, eighth,
and ninth rotation elements of the third planetary gear set are a
third sun gear, a third ring gear, and a third planetary carrier,
respectively, and the tenth, eleventh, and twelfth rotation
elements of the fourth planetary gear set are a fourth sun gear, a
fourth planetary carrier, a fourth ring gear, respectively.
4. The planetary gear train of claim 2, further comprising: a first
clutch that selectively connects the first shaft and the input
shaft; a second clutch that selectively connects the third shaft
and the input shaft; a third clutch that selectively connects the
sixth shaft and the eighth shaft; a first brake that selectively
connects the first shaft and the transmission housing; a second
brake that selectively connects the fourth shaft and the
transmission housing; and a third brake that selectively connects
the fifth shaft and the transmission housing.
5. A planetary gear train of an automatic transmission for a
vehicle, comprising: an input shaft configured to receive power of
an engine; an output shaft configured to output power; a first
planetary gear set having first, second, and third rotation
elements; a second planetary gear set having fourth, fifth, and
sixth rotation elements; a third planetary gear set having seventh,
eighth, and ninth rotation elements; and a fourth planetary gear
set having tenth, eleventh, and twelfth rotation elements, wherein
the input shaft is directly connected with the eleventh rotation
element, the output shaft is directly connected with the eighth
rotation element, wherein the first rotation element is directly
connected with the fourth rotation element and is selectively
connected with the input shaft or is selectively connected with the
transmission housing, wherein the second rotation element is
directly connected with the sixth rotation element, the seventh
rotation element, and the tenth rotation element, wherein the third
rotation element is selectively connected with the input shaft, and
wherein the twelfth rotation element is selectively connected with
the eighth rotation element.
6. The planetary gear train of claim 5, wherein the fifth rotation
element and the ninth rotation element each are selectively
connected with a transmission housing.
7. The planetary gear train of claim 5, wherein the first, second,
and third rotation elements of the first planetary gear set are a
first sun gear, a first planetary carrier, and a first ring gear,
respectively, wherein the fourth, fifth, and sixth rotation
elements of the second planetary gear set are a second sun gear, a
second planetary carrier, and a second ring gear, respectively,
wherein the seventh, eighth, and ninth rotation elements of the
third planetary gear set are a third sun gear, a third ring gear,
and a third planetary carrier, respectively, and wherein the tenth,
eleventh, and twelfth rotation elements of the fourth planetary
gear set are a fourth sun gear, a fourth planetary carrier, and a
fourth ring gear, respectively.
8. The planetary gear train of claim 6, further comprising: a first
clutch that selectively connects the first rotation element and the
input shaft; a second clutch that selectively connects the third
rotation element and the input shaft; a third clutch that
selectively connects the eighth rotation element and the twelfth
rotation element; a first brake that selectively connects the first
rotation element and the transmission housing; a second brake that
selectively connects the fourth rotation element and the
transmission housing; and a third brake that selectively connects
the fifth rotation element and the transmission housing.
Description
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to and the benefit of Korean
Patent Application No. 10-2016-0031663 filed in the Korean
Intellectual Property Office on Mar. 16, 2016, the entire contents
of which are incorporated herein by reference.
BACKGROUND
(a) Field of the Invention
The present invention relates to an automatic transmission for a
vehicle and more particularly, to a planetary gear train of an
automatic transmission for a vehicle that improves a power delivery
performance and enhances fuel consumption by implementing at least
forward nine-speed with a reduced configuration and reduces running
noise of the vehicle by utilizing a driving point in a low rotation
speed range of an engine.
(b) Description of the Related Art
Generally, in an automatic transmission field research on a
multistage of a gear shift stage has been conducted to enhance fuel
consumption and to maximize drivability of a vehicle. In
particular, an increase of the cost of oil price has resulted in
requirements to enhance fuel consumption of a vehicle. Accordingly,
research that reduces a weight and enhances fuel consumption of an
engine has been conducted to reduce the size of the engine. For
example research on an automatic transmission has been conducted to
simultaneously secure drivability and fuel consumption competitive
power through a multistage of a gear shift stage. However, in the
automatic transmission, as a number of gear shift stage increases,
the internal component number of the planetary gear set number
increases. In other words, the length of the transmission increases
and a mounting ability, a production cost, a weight, and power
delivery efficiency may be reduced.
Therefore, in the automatic transmission, to increase a fuel
consumption of the automatic transmission, an enhancement effect
through a multistage of a gear shift stage requires development of
a planetary gear train that induces maximum efficiency with the
minimal number of required components. Accordingly, an automatic
transmission implements a shift of 8-speed or greater to be mounted
within a vehicle. Research and development of a planetary gear
train that implements a gear shift stage of 8-speed or greater has
been continuously required.
However, a general 8-speed or more of automatic transmission is
typically formed with three or four planetary gear sets and five or
six control elements (e.g., friction element). In other words the
total length is increased and may degrade a mounting ability. To
form a gear shift stage of an automatic transmission in a
multistage, a double row structure that disposes a planetary gear
set on a planetary gear set has been adapted or a dog clutch may be
applied instead of a wet control element. However, structure may be
limited and a shift feel may be degraded due to application of the
dog clutch.
The above information disclosed in this section is merely for
enhancement of understanding of the background of the invention and
therefore it may contain information that does not form the prior
art that is already known in this country to a person of ordinary
skill in the art.
SUMMARY
The present invention provides a planetary gear train of an
automatic transmission for a vehicle with a gear shift stage of at
least forward nine-speed or more and at least reverse one-speed or
more with a reduced configuration and reduces running noise of the
vehicle by using a driving point in a lower rotation speed range of
an engine.
An exemplary embodiment of the present invention provides a
planetary gear train of an automatic transmission for a vehicle
that may include an input shaft configured to receive power of an
engine; an output shaft configured to output power; a first
planetary gear set having first, second, and third rotation
elements; a second planetary gear set having fourth, fifth, and
sixth rotation elements; a third planetary gear set having seventh,
eighth, and ninth rotation elements; a fourth planetary gear set
having tenth, eleventh, and twelfth rotation elements; a first
shaft that connects the first rotation element and the fourth
rotation element and is selectively connected with the input shaft
or selectively connected with a transmission housing; a second
shaft that connects the second rotation element and the sixth
rotation element and the seventh rotation element and the tenth
rotation element; a third shaft connected with the third rotation
element and selectively connected with the input shaft; a fourth
shaft connected with the fifth rotation element; a fifth shaft
connected with the ninth rotation element; a sixth shaft connected
with the eighth rotation element and directly connected with the
output shaft; a seventh shaft connected with the eleventh rotation
element and directly connected with the input shaft; and an eighth
shaft connected with the twelfth rotation element and selectively
connected with the sixth shaft.
The fourth shaft and the fifth shaft each may be selectively
connected with a transmission housing. The first, second, and third
rotation elements of the first planetary gear set may be a first
sun gear, a first planetary carrier, and a first ring gear,
respectively. The fourth, fifth, and sixth rotation elements of the
second planetary gear set may be a second sun gear, a second
planetary carrier, and a second ring gear, respectively. The
seventh, eighth, and ninth rotation elements of the third planetary
gear set may be a third sun gear, a third ring gear, and a third
planetary carrier, respectively, and the tenth, eleventh. The
twelfth rotation elements of the fourth planetary gear set may be a
fourth sun gear, a fourth planetary carrier, a fourth ring gear,
respectively.
The planetary gear train may further include a first clutch that
selectively connects the first shaft and the input shaft, a second
clutch that selectively connects the third shaft and the input
shaft, a third clutch that selectively connects the sixth shaft and
the eighth shaft, a first brake that selectively connects the first
shaft and the transmission housing, a second brake that selectively
connects the fourth shaft and the transmission housing and a third
brake that selectively connects the fifth shaft and the
transmission housing.
Accordingly, by combining four planetary gear sets that are formed
with a simple planetary gear set with six control elements, a gear
shift stage of at least forward nine-speed or more and a gear shift
stage of at least reverse one-speed or more may be implemented.
Further, according to the present invention, by forming a gear
shift stage of an automatic transmission in a multistage, a gear
shift stage appropriate to a rotation speed of an engine may be
implemented. In particular, running noise of a vehicle may be
reduced by utilizing a driving point in a lower rotation speed
range of the engine. Further, according to the present invention,
engine driving efficiency may be maximized with a high efficiency
multistage, and a power delivery performance and fuel consumption
may be improved.
In addition, an effect that may be obtained or estimated due to an
exemplary embodiment of the present invention is directly or
implicitly described in a detailed description of an exemplary
embodiment of the present invention. That is, various effects that
are estimated according to an exemplary embodiment of the present
invention will be described within a detailed description to be
described later.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other objects, features and other advantages of the
present invention will be more clearly understood from the
following detailed description when taken in conjunction with the
accompanying drawings, in which:
FIG. 1 is an exemplary schematic diagram illustrating a planetary
gear train according to an exemplary embodiment of the present
invention; and
FIG. 2 is an exemplary table illustrating operation on a gear shift
stage basis of a control element that is applied to a planetary
gear train according to an exemplary embodiment of the present
invention.
DETAILED DESCRIPTION
Hereinafter, an exemplary embodiment of the present invention will
be described in detail with reference to the accompanying drawings.
While the invention will be described in conjunction with exemplary
embodiments, it will be understood that present description is not
intended to limit the invention to those exemplary embodiments. On
the contrary, the invention is intended to cover not only the
exemplary embodiments, but also various alternatives,
modifications, equivalents and other exemplary embodiments, which
may be included within the spirit and scope of the invention as
defined by the appended claims.
The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
the invention. As used herein, the singular forms "a", "an" and
"the" are intended to include the plural forms as well, unless the
context clearly indicates otherwise. It will be further understood
that the terms "comprises" and/or "comprising," when used in this
specification, specify the presence of stated features, integers,
steps, operations, elements, and/or components, but do not preclude
the presence or addition of one or more other features, integers,
steps, operations, elements, components, and/or groups thereof. As
used herein, the term "and/or" includes any and all combinations of
one or more of the associated listed items. For example, in order
to make the description of the present invention clear, unrelated
parts are not shown and, the thicknesses of layers and regions are
exaggerated for clarity. Further, when it is stated that a layer is
"on" another layer or substrate, the layer may be directly on
another layer or substrate or a third layer may be disposed there
between.
Unless specifically stated or obvious from context, as used herein,
the term "about" is understood as within a range of normal
tolerance in the art, for example within 2 standard deviations of
the mean. "About" can be understood as within 10%, 9%, 8%, 7%, 6%,
5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated
value. Unless otherwise clear from the context, all numerical
values provided herein are modified by the term "about."
It is understood that the term "vehicle" or "vehicular" or other
similar term as used herein is inclusive of motor vehicle in
general such as passenger automobiles including sports utility
vehicles (SUV), buses, trucks, various commercial vehicles,
watercraft including a variety of boats, ships, aircraft, and the
like and includes hybrid vehicles, electric vehicles, combustion,
plug-in hybrid electric vehicles, hydrogen-powered vehicles and
other alternative fuel vehicles (e.g. fuels derived from resources
other than petroleum).
FIG. 1 is an exemplary schematic diagram illustrating a planetary
gear train according to an exemplary embodiment of the present
invention. Referring to FIG. 1, a planetary gear train according to
an exemplary embodiment of the present invention may include first,
second, third, and fourth planetary gear sets PG1, PG2, PG3, and
PG4 disposed on the same shaft line, an input shaft IS, an output
shaft OS, eight shafts TM1-TM8 connected with each rotation element
of the first, second, third, and fourth planetary gear sets PG1,
PG2, PG3, and PG4, three clutches C1-C3 and three brakes B1-B3,
which are a control element, and a transmission housing H.
Rotation power from an engine input from the input shaft IS may be
shifted by a mutual compensation operation of the first, second,
third, and fourth planetary gear sets PG1, PG2, PG3, and PG4 to be
output through the output shaft OS. For example, the planetary gear
sets may be disposed in order of the first, second, third, and
fourth planetary gear sets PG1, PG2, PG3, and PG4 from the engine
side. The input shaft IS may be an input member, and a torque of
rotation power from a crankshaft of the engine may be converted and
input using a torque converter. The output shaft OS may be an
output member and may be disposed on the same shaft line as that of
the input shaft IS to deliver a shifted driving torque to a drive
shaft using a differential apparatus.
The first planetary gear set PG1 may be a single pinion planetary
gear set and may include a first sun gear S1, which is a first
rotation element N1, a first planetary carrier PC1, which is a
second rotation element N2 configured to support a rotation of a
first pinion gear P1 externally engaged with the first sun gear S1,
which is the first rotation element N1, and a first ring gear R1,
which is a third rotation element N3 internally engaged with the
first pinion gear P1. The second planetary gear set PG2 may be a
single pinion planetary gear set and may include a second sun gear
S2, which is a fourth rotation element N4, a second planetary
carrier PC2, which is a fifth rotation element N5 to support a
rotation of a second pinion gear P2 that may be externally engaged
with the second sun gear S2, which is the fourth rotation element
N4, and a second ring gear R2, which is a sixth rotation element N6
that may be internally engaged with the second pinion gear P2.
The third planetary gear set PG3 may be a double pinion planetary
gear set and may include a third sun gear S3, which is a seventh
rotation element N7, a third ring gear R3, which is an eighth
rotation element N8 internally engaged with an external pinion of a
pair of third pinions P3 that externally engaged with the third sun
gear S3, which is the seventh rotation element N7, and a third
planetary carrier PC3, which is a ninth rotation element N9 that to
support the third pinion P3 that may be externally engaged with the
third sun gear S3, which is the seventh rotation element N7. The
fourth planetary gear set PG4 may be a single pinion planetary gear
set and may include a fourth sun gear S4, which is a tenth rotation
element N10, a fourth planetary carrier PC4, which is an eleventh
rotation element N11 to support a rotation of a fourth pinion gear
P4 that may be externally engaged with the fourth sun gear S4,
which is the tenth rotation element N10, and a fourth ring gear R4,
which is a twelfth rotation element N12 that may be internally
engaged with the fourth pinion gear P4.
Further, in the first, second, third, and fourth planetary gear
sets PG1, PG2, PG3, and PG4, the first rotation element N1 may be
directly connected with the fourth rotation element N4. The second
rotation element N2 may be directly connected with the sixth
rotation element N6, the seventh rotation element N7, and the tenth
rotation element N10. The first, second, third, and fourth
planetary gear sets PG1, PG2, PG3, and PG4 may be configured to
operate while holding total eight shafts TM1-TM8.
A configuration of the eight shafts TM1-TM8 is described in detail
as follows. The eight shafts TM1-TM8 may be a rotation member that
delivers power while rotating together with a rotation element that
may be connected to directly connect or to selectively connect a
plurality of rotation elements among rotation elements of the
planetary gear sets PG1, PG2, PG3, and PG4 and may be a fixing
member that may directly connect and fixes the rotation element to
the transmission housing H.
The first shaft TM1 may directly connect the first rotation element
(e.g., N1; first sun gear S1) and the fourth rotation element
(e.g., N4; second sun gear S2) and may be configured to operate as
a selective input element while being selectively connected with
the input shaft IS or may be configured to operate as a selective
fixing element while being selectively connected with the
transmission housing H. The second shaft TM2 may directly connect
the second rotation element (e.g., N2; first planetary carrier
PC1), the sixth rotation element (e.g., N6; second ring gear R2),
the seventh rotation element (e.g., N7; third sun gear S3), and the
tenth rotation element (e.g., N10; fourth sun gear S4).
The third shaft TM3 may be directly connected with the third
rotation element (e.g., N3; first ring gear R1) and may operate as
a selective input element while being selectively connected with
the input shaft IS. The fourth shaft TM4 may be directly connected
with the fifth rotation element (e.g., N5; second planetary carrier
PC2) and may operate as a selective input element while being
selectively connected with the transmission housing H. The fifth
shaft TM5 may be directly connected with the ninth rotation element
(e.g., N9; third planetary carrier PC3) and may operate as a
selective input element while being selectively connected with the
transmission housing H.
The sixth shaft TM6 may be directly connected with the eighth
rotation element (e.g., N8; third ring gear R3) and may be directly
connected with the output shaft OS to operate as an output element.
The seventh shaft TM7 may be directly connected with the eleventh
rotation element (e.g., N11; fourth planetary carrier PC4) and may
be directly connected with the input shaft IS to operate as an
input element. The eighth shaft TM8 may be directly connected with
the twelfth rotation element (e.g., N12; fourth ring gear R4) and
may be selectively connected with the sixth shaft TM6.
Among the eight shafts TM1-TM8, in a portion including the input
shaft IS and the output shaft OS and that mutually selectively
connects shafts, three clutches C1, C2, and C3 may be disposed.
Further, among the eight shafts TM1-TM8, in a portion in which the
shaft and the transmission housing H are selectively connected,
three brakes B1, B2, and B3 may be disposed. In other words, a
disposition location of the three clutches C1-C3 and three brakes
B1-B3 is described as follows. The first clutch C1 may be disposed
between the input shaft IS and the first shaft TM1 to selectively
connect the input shaft IS and the first shaft TM1 to generate
power. The second clutch C2 may be disposed between the input shaft
IS and the third shaft TM3 to selectively connect the input shaft
IS and the third shaft TM3 to generate power. The third clutch C3
may be disposed between the sixth shaft TM6 and the eighth shaft
TM8 to selectively connect the sixth shaft TM6 and the eighth shaft
TM8 to generate power.
The first brake B1 may be disposed between the first shaft TM1 and
the transmission housing H to selectively connect and fix the first
shaft TM1 to the transmission housing H. The second brake B2 may be
disposed between the fourth shaft TM4 and the transmission housing
H to selectively connect and fix the fourth shaft TM4 to the
transmission housing H. The third brake B3 may be disposed between
the fifth shaft TM5 and the transmission housing H to selectively
connect and fix the fifth shaft TM5 to the transmission housing H.
In the foregoing description, each control element may be formed
with the first, second, and third clutches C1, C2, and C3 and the
first, second, and third brakes B1, B2, and B3 may be formed with a
multiplate type hydraulic pressure friction coupling unit that is
friction coupled by a hydraulic pressure.
FIG. 2 is an exemplary table illustrating operation on each gear
shift stage basis of a control element that may be applied to a
planetary gear train according to an exemplary embodiment of the
present invention. Referring to FIG. 2, in each gear shift stage of
the planetary gear train according to an exemplary embodiment of
the present invention, among the first, second, and third clutches
C1, C2, and C3 and the first, second, and third brakes B1, B2, and
B3, which are a control element, while three elements operate, a
shift of reverse one-speed and forward nine-speed may be performed,
and a shift process is described as follows.
In a forward one-speed gear shift stage D1, the second clutch C2
and the second and third brakes B2 and B3 may be operated
simultaneously with a gear ratio of about 4.493. Accordingly when
the third shaft TM3 is connected with the input shaft IS by
operation of the second clutch C2, rotation power of the input
shaft IS may be input to the third and seventh shafts TM3 and TM7.
The fourth and fifth shafts TM4 and TM5 may be shifted to a forward
one-speed by a mutual compensation operation of each shaft while
operating as a fixing element by operation of the second and third
brakes B2 and B3 may be configured to output power through the
output shaft OS connected with the sixth shaft TM6.
In a forward two-speed gear shift stage D2, the second clutch C2
and the first and third brakes B1 and B3 may be operated
simultaneously operated with a gear ratio of about 2.798.
Accordingly, when the third shaft TM3 is connected with the input
shaft IS by operation of the second clutch C2, rotation power of
the input shaft IS may be input to the third and seventh shafts TM3
and TM7. The first and fifth shafts TM1 and TM5 may be shifted to a
forward two-speed by a mutual compensation operation of each shaft
while operating as a fixing element by operation of the first and
third brakes B1 and B3 may be configured to output power through
the output shaft OS connected with the sixth shaft TM6.
In a forward three-speed gear shift stage D3, the first and second
clutches C1 and C2 and the third brake B3 may be operated
simultaneously with a gear ratio of about 1.950. Accordingly, when
the first shaft TM1 is connected with the input shaft IS by
operation of the first clutch C1 and when the third shaft TM3 is
connected with the input shaft IS by operation of the second clutch
C2, rotation power of the input shaft IS may be input to the first,
third, and seventh shafts TM1, TM3, and TM7. The fifth shaft TM5
may be shifted to a forward three-speed by a mutual compensation
operation of each shaft while operating as a fixing element by
operation of the third brake B3 may be configured to output power
through the output shaft OS connected with the sixth shaft TM6.
In a forward four-speed gear shift stage D4, the first and third
clutches C1 and C3 and the third brake B3 may be operated
simultaneously with a gear ratio of about 1.380. Accordingly, when
the first shaft TM1 is connected with the input shaft IS by
operation of the first clutch C1 and when the sixth shaft TM6 is
connected with the eighth shaft TM8 by operation of the third
clutch C3, rotation power of the input shaft IS may be input to the
first and seventh shafts TM1 and TM7. The fifth shaft TM5 may be
shifted to a forward four-speed by a mutual compensation operation
of each shaft while operating as a fixing element by operation of
the third brake B3 may be configured to output power through the
output shaft OS connected with the sixth shaft TM6.
In a forward five-speed gear shift stage D5, the first, second, and
third clutches C1, C2, and C3 may be simultaneously with a gear
ratio of about 1.000. Accordingly, when the first shaft TM1 is
connected with the input shaft IS by operation of the first clutch
C1 and when the third shaft TM3 is connected with the input shaft
IS by operation of the second clutch C2 and when the sixth shaft
TM6 is connected with the eighth shaft TM8 by operation of the
third clutch C3, rotation power of the input shaft IS may be input
to the first, third, and seventh shafts TM1, TM3, and TM7.
Accordingly, when first, second, third, and fourth planetary gear
sets PG1, PG2, PG3, and PG4 integrally rotate, the first, second,
third, and fourth planetary gear sets PG1, PG2, PG3, and PG4 may be
shifted to a forward five-speed that may be configured to output a
similar value as an input value to output power through the output
shaft OS connected with the sixth shaft TM6.
In a forward six-speed gear shift stage D6, the second and third
clutches C2 and C3 and the first brake B1 may be simultaneously
operated with a gear ratio of 0.832. Accordingly, when the third
shaft TM3 is connected with the input shaft IS by operation of the
second clutch C2 and when the sixth shaft TM6 is connected with the
eighth shaft TM8 by operation of the third clutch C3, rotation
power of the input shaft IS may be input to the third and seventh
shafts TM3 and TM7. The first shaft TM1 may be shifted to a forward
six-speed by a mutual compensation operation of each shaft when
configured to operate as a fixing element by adjustment of the
first brake B1 to output power through the output shaft OS
connected with the sixth shaft TM6.
In a forward seven-speed gear shift stage D7, the second and third
clutches C2 and C3 and the second brake B2 may be operated
simultaneously with a gear ratio of about 0.726. Accordingly, when
the third shaft TM3 is connected with the input shaft IS by
operation of the second clutch C2 and when the sixth shaft TM6 is
connected with the eighth shaft TM8 by operation of the third
clutch C3, rotation power of the input shaft IS may be input to the
third and seventh shafts TM3 and TM7. The fourth shaft TM4 may be
shifted to a forward seven-speed by a mutual compensation operation
of each shaft when configured to operate as a fixing element by
operation of the second brake B2 that may be configured to output
power through the output shaft OS connected with the sixth shaft
TM6.
In a forward eight-speed gear shift stage D8, the third clutch C3
and the first and second brakes B1 and B2 may be operated
simultaneously with a gear ratio of about 0.600. Accordingly, when
the sixth shaft TM6 is connected with the eighth shaft TM8 by
operation of the third clutch C3, rotation power of the input shaft
IS may be input to the seventh shaft TM7. The first and fourth
shafts TM1 and TM4 may be shifted to a forward eight-speed by a
mutual compensation operation of each shaft while simultaneously
operating as a fixing element by operation of the first and second
brakes B1 and B2 that may be configured to output power through the
output shaft OS connected with the sixth shaft TM6.
In a forward nine-speed gear shift stage D9, the first and third
clutches C1 and C3 and the second brake B2 may be operated
simultaneously with a gear ratio of about 0.500. Accordingly, when
the first shaft TM1 is connected with the input shaft IS by
operation of the first clutch C1 and when the sixth shaft TM6 is
connected with the eighth shaft TM8 by operation of the third
clutch C3, rotation power of the input shaft IS may be input to the
first and seventh shafts TM1 and TM7. The fourth shaft TM4 may be
shifted to a forward nine-speed by a mutual compensation operation
of each shaft while operating as a fixing element by operation of
the second brake B2 that may be configured to output power through
the output shaft OS connected with the sixth shaft TM6.
In a reverse shift stage REV, the first clutch C1 and the second
and third brakes B2 and B3 may be operated simultaneously operated
with a gear ratio of about -3.900. Accordingly, when the first
shaft TM1 is connected with the input shaft IS by operation of the
first clutch C1, rotation power of the input shaft IS may be input
to the first and seventh shafts TM1 and TM7. The fourth and fifth
shafts TM4 and TM5 may be shifted to the reverse by a mutual
compensation operation of each shaft while operating as a fixing
element by operation of the second and third brakes B2 and B3 that
may be configured to output power through the output shaft OS
connected with the sixth shaft TM6.
As described above, a planetary gear train according to an
exemplary embodiment of the present invention may be configured to
operate four planetary gear sets PG1, PG2, PG3, and PG4 to realize
a gear shift stage of at least forward nine-speed or more and at
least reverse one-speed or more by an adjustment of three clutches
C1, C2, and C3 and three brakes B1, B2, and B3.
Additionally, by forming a gear shift stage of an automatic
transmission in a multistage, a planetary gear train according to
an exemplary embodiment of the present invention may implement a
gear shift stage appropriate to a rotation speed of an engine and
may improve running silence of a vehicle by using a driving point
in a low rotation speed range of the engine. Further, by forming an
automatic transmission in a multistage, a planetary gear train
according to an exemplary embodiment of the present invention may
maximize engine driving efficiency and improve a power delivery
performance and fuel consumption.
While this invention has been described in connection with what is
presently considered to be 1 exemplary embodiments, it is to be
understood that the invention is not limited to the disclosed
exemplary embodiments, but, on the contrary, is intended to cover
various modifications and equivalent arrangements included within
the spirit and scope of the appended claims.
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